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Publication numberUS3852421 A
Publication typeGrant
Publication dateDec 3, 1974
Filing dateSep 20, 1971
Priority dateMar 23, 1970
Publication numberUS 3852421 A, US 3852421A, US-A-3852421, US3852421 A, US3852421A
InventorsKoyanagi S, Ogawa K, Onda Y, Yamamoto A
Original AssigneeShinetsu Chemical Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Excipient and shaped medicaments prepared therewith
US 3852421 A
Abstract
The excipient comprises hydroxy alkyl cellulose or hydroxy alkyl alkyl cellulose, wherein the average number of substituted moles of hydroxy group in glucose per anhydrous glucose unit is from 0.1 to 1.30; the average number of substituted moles of hydroxyalkyl groups per anhydrous glucose unit is from 0.05 to 1.00; and the average number of substituted moles of alkyl groups per anhydrous glucose unit is from 0 to 1.00. When the excipient is mixed with a medicament and the resultant mixture is compressed, hard, readily disintegratable tablets are produced.
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Description  (OCR text may contain errors)

States fi Koyanagi et a1.

EXCIPIENT AND SHAPED MEDICAMENTS PREPARED THEREWITH Inventors: Shunichi Koyanagi; Kinya Ogawa;

Yoshiro Onda, all of Niigata-ken; Akira Yamamoto, Naoetsu, all of Japan Assignee: Shinetsu Chemical (Jompany,

- Tokyo, Japan Filed: Sept. 20, 1971 Appl. No.: 182,226

Related U.S. Application Data Continuation-impart of Ser. No. 80,203, Oct. 12,

' 1970, abandoned.

Foreign Application Priority Data y a ga vo Japan 45-34203 U.S. C1 424/94, 424/280, 424/361,

424/362, 260/231 Int. Cl. A6lj 3/10 Field of Search 424/361, 362; 260/231 References Cited UNITED STATES PATENTS 9/1958 Kennon et a1. 260/232 1 Dec. 3, 1974 3,424,842 l/1969 Nurnberg 424/94 3,679,794 7/1972 Bentholm et a1. 424/148 OTHER PUBLICATIONS GA. 75 number 40419Y (1971). GA. 75 number 25412X (1971). GA. 75 number 40356A (1971). GA. 71 number 4224811 (1969). GA. 69 number 61529A (1968).

Primary Examiner-Shep K. Rose Attorney, Agent, or Firm-Bierman & Bierman 5 7] ABSTRACT 7 Claims, No Drawings EXCIPIENT AND'SHAPED NEDICAMENTS PREPARED THEREWITH shaped medicaments dissolves in the water, starchifies,

in the human body, a method for producing such readily disintegratable solid bodies and to the readily disintegratable solid medicament containing bodies that are produced with said excipient.

In shaping medicaments into tablets, pills, granules or pellets, a certain amount of a medicament is usually mixed with one or more kinds of additives which function as a shaping agent, a binding agent or a disintegrating agent. The additives which are known in the art all have faults. No satisfactory additives have as yet been discovered. For example, starchand micro-crystalline cellulose which are primarily employed as shaping agents will not work as disintegrating agents unless they are used in a large quantity relative to the quantity of the medicament. In the case of tablets, the increase in the relative amount of such substances not only reduces tablet hardness and causes sticking, but also makes necessary an increase in tablet size. This makes it difficult to swallow the tablets. Gelatin cannot be used in shaping white or pale-colored tablets, because its color is not pure white. Moreover, disintegrating agents suchas sodium or calcium salts of carboxymethylcellulose or cellulose glycollic acid and its calcium salt, which are employed together with the shaping agent, exemplified by the above-mentioned starch,

microcrystalline cellulose and gelatin, or hydroxypropyl starch, methylcellulose, hydroxypropyl cellulose, and polyvinylpyrrolidone, remarkably reducethe hardness" of the tablets. Moreover, because of their acidity or dissociating property, they may, depending on the kind of medicament employed, react with the medicav ment, thereby deteriorating its medicinal property. Thus, they do not possess a wide range of application.

It has been recently proposed to use a methyl cellulose having a low degree of substitution. However, it is difficult to completely remove the large quantity of sodium chloride-produced as a by-produ ct in the production of this material. The chloride ion, arising from this sodium chloride,-inevitably corrodes the manufacturingapparatus and reacts with the medicament, thereby deterioble in water. Therefore when in the course of disintegration 'medicaments containing it come in contact with water, the cellulose ether on the surface of the and forms a film which acts to prevent further penetration of water into the inner part of the shaped medicaments. Consequently, it takes a long time for the shaped medicaments to disintegrate. In contrast thereto, hydroxyalkyl cellulose or hydroxyalkyl alkyl cellulose, in which the number of hydroxyalkyl radicalsubstituted moles per glucose unit is within the abovedisclosed range is insoluble or barely soluble in water. Therefore, water easily penetrates into a shaped medicament containing it as a binder, causing it to swell. This helps to rapidly disintegrate the shaped medicament. Furthermore, such hydroxyalkyl cellulose, be-

7 rating its properties. These are serious disadvantages. I

cause it contains hydroxyl radical. in its molecule, imparts to the shaped medicaments a. high degree of hardness that is not attainable with other cellulose ethers. This accounts for the fact, as discovered by the present inventors, that these materials work both as an excellent shaping agent and as a binder.

The hydroxyalkyl cellulose and/or hydroxyalkyl alkyl cellulose employed in the present invention is exemplified by hydroxyethyl cellulose hydroxypropyl cellulose, hydroxybutyl ethylcellulose, hydroxybutyl methylcellulose, 7 hydroxypropyl ethylcellulose, hydroxypropyl methylcellulose, hydroxyethyl ethylcellulose, hydroxyethyl methylcellulose, and mixtures thereof. In order to attain the objects of the instant invention, the average number of substituted moles of hydroxyalkyl and alkyl groups in glucose per anhydrous glucose unit should be from 0.1 to 1.30, preferably from 0.2 to 1.0; the average number of substituted moles of hydroxyalkyl,

drous glucose unit should be from 0 ml .00, preferably less than 0.80. I

For the purpose of attaining the object of the inventionmore advantageously, the particle size of at least by weight of the hydroxyalkyl cellulose or hydroxyalkyl alkylcelluloseshould be at most p, or more preferably at most 80a, with the apparent density thereof being from 0.3 to 0.8 g/cc, or more preferably from 0.5 -0.8 g/cc. It is advisable to mix such hydroxyalkyl cellulose or hydroxyalkylalkylcellulose with the medicaments and shape the mixture thus obtained by the dry and direct compression method. The resultant shaped products will be superiorin gloss, hardness and disintegration, and will hardly suffer any abrasion.

The cellulose ethers employed in the practice of the invention are prepared by the'well-known conventional method which consists of '(i) dipping pulp in a 10-30% aqueous solution of caustic soda and pressing it into alkali cellulose, (ii) charging the alkali cellulose together with alkylene oxide into a reactor and reacting same therein at 20-50C and under pressure, for Z-S-hours, (iii) thereafter neutralizing by washing the hydroxyalkyl cellulose or hydroxyalkyl .alkylcellulose thus prepared with alkali, (iv) then further washing the neutralized hydroxyalkyl cellulose or hydroxyalkyl alkylcellulose with water and pulverizing it, or cooling to 010C the neutralized hydroxyalkyl cellulose or hydroxyalkyl alkylcellulose containing from 30 to 70% of water, drying it, then pulverizing it. In order to make its particle size and apparent density as given above, the pulverized cellulose ether may be further ground by means of a device such as an atomizer. Hydroxyalkyl cellulose or hydroxyalkyl alkylcellulose powder thus The shaping of the medicaments in accordance with 5 Bwmvaleryl urea the present invention may be carried out by prior art known methods excepting that the above-mentioned cellulose ether powder is employed. The cellulose ether is added to the medicament in the ratio of from 1 to 50%, preferably from to 30% based on the weight of the solid dosage form. The mixture may then be shaped into tablets, pills or granules by such known methods, as the dry method, the wet method, etc. The disintegration time of the shaped medicament can be controlled at will, irrespective of the nature of the medicament', by varying the quantity of the cellulose ether powder employed within the prescribed range. When mixing the cellulose ether and the medicament, lubricating and polishing agents such as, for example, talc, wax or a metallic salt of stearic acid may be added. One may also add along with the lubricating and polishing agents, known shaping or binding agents, e.g., lactose, starch, cane sugar, gum arabic, tragacanth gum, gelatin, water and alcohol, in amounts such as will not deteriorate the properties of said cellulose ether.

in the examples given below, parts and are all parts and by weight. The apparent density of the cellulose ether powder, the disintegration (given in time) and the hardness of the tablets were measured under the following conditions.

Apparent density:

50 g of the sample (cellulose ether powder) was put in a 250 cc measuring cylinder, and shaken in a shaker for 3 minutes. The cubic volume (cc) of the sample in the cylinder was then measured and the value obtained was employed in calculating the apparent density of the sample.

Disintegration:

Disintegration of a tablet prepared of the medicament and the cellulose ether powder was measuredby GeneralTest Method 25 of the Japanese Pharmacopeia.

Hardness: i

A tablet like the one given above was put between two plates and compressed. The pressure immediately before the tablet was disintegrated was determined by the Monsanto hardness tester and was employed'to denote its hardness. It should be noted that as used in the examples the abbreviation M.S. means the average number of moles of the respective radical combined with the cellulose per anhydroglucose unit.

EXAMPLE 1.

i. Hydroxypropyl cellulose (HPC, M.S.:0.4), having an apparent density of 0.55, at least 95% of which had a particle size of 74p. or less, the number of hydroxypropyl radical-substituted moles per glucoseunit being 0.4, and (ii) starch were each mixed with the other ingredients given in Table l. The mixtures were tableted by dry and direct compression method (pressure 300 kg/cm) into tablets whereby Samples 1 and 2 were respectively obtained. The average disintegration time and hardness of these samples were as given in Table Table 1 Sample No. 1 (Present invention) 2 (Control) 200 mg 200 mg Lactose 40 do. 40 do. Starch 0 1 12 do. Carbowax 6,000 6 mg 6 do. HPC. M.S.: 0.4 U2 do. 0 Total weight (per tablet) 358 mg 358 mg (Trade mark for a lubricating and polishing agent manufactured by Union Carbide Corporation.)

(i) Hydroxypropyl cellulose (HPC, M.S.:3.2), having an apparent density of 0.45 g/cc, at least 90% of which had a particle size of 250p. or less, the number of hydroxypropyl radical-substituted moles per glucose unit being 3.2, and (ii) hydroxypropyl cellulose (HPC, M.S.:0.7), having an apparent density of 0.60 g/cc, at least of which had a particle size of 74p. or less, the number of hydroxypropyl radical-substituted moles per glucose unit being 0.7, were each mixed with the other ingredients given in Table 3, and tableted by dry and direct compression method (pressure: 500 kglcm into tablets, whereby Samples 3 and 4 were obtained. The average disintegration time and hardness of these samples were as given in Table 4.

Table 3 Sample No. 3 (Present invention) 4 (Control) Vitamin C l00 mg mg Lactose lOO do. 100 do. Magnesium stearate I do. l do. HPC. M.S.: 3.2 0 20 do. HPC, M.S.:'0.7 20 do. 0 do. Total weight (per tablet) 22l mg 22l mg Table 4 Sample No. 3 4

Hardness (kg) 9 kg 8 kg Average disintegration time 40 Sec 5 min.

1 or over EXAMPLE 3.

(i) Hydroxyehtyl cellulose (HEC,M.S.:0.3 having an apparent density of 0.60 g/cc, at least 95% of which had a particle size of 74a or less, the number of hydroxyethyl radical-substituted moles per glucose unit being 0.3, and (ii) calcium salt of carboxymethyl cellulose (CMC-Ca), havingan apparent density of 0.80 g/cc, at

Samples 5 and 6 were obtained. The properties of these samples are given in Table 6.

(i) Hydroxypropyl cellulose (HPC, M.S.:0.25), hav- 20 given in Table 9.

EXAMPLE 5.

i llydroxyetliyl methylcellulose (MS. of hydroxyethyl radical: 0.25, and MS. of methoxyl group: 0.25, and exhibiting when dissolved in an amount of 2 to aqueous solution of sodium hydroxide a viscosity of 10 cps. at C), was pulverized on a high-speed hammer mill. Three kinds of samples were thereby obtained No. 9 (subjected to one pulverizing), No. 10 (subjected to two pulverizings), and No. ll (subjected to three pulverizings), as given in Table 9'. V

250 parts of pancreatin, 7 parts of polyvinylpyrrolidone, and 1 part of calcium stearate were added to 42 parts of each of the samples and to 42 parts of microcrystalline cellulose as a control. The resultant mixtures were uniformly mixed, and tableted by means of a direct compression-type tableting machine (pressures: 200 kg/mm into 300 mg tablets. The average disintegration time and hardness of the tablets ,were as Table 9 Present Invention Control Sample No. 9 l l 12 Apparent density (g/cc) 0.43 0.48 0.55 Particle size Over 24611. 1.5 3.5 Distribution (k Under 74 91.0 Result of Average 120 90 60 over the test disintegration 300 time (seconds Hardness 8.8 11.5 13.2 12.1 (Kg) mg an apparent density of 0.53 g/cc, at least 95% of EXAMPLE which had a particle size of 74 1. or less, the number of 40 hydroxypropyl radical-substituted moles per glucose unit being 0.25, and (ii) methyl cellulose (MC, M.S.:0.5), having an apparent density of 0.53 g/cc, at least 95% of which had a particle size of 74p. or less, the

degree of methoxy radical substitution being 0.5, were each mixed with the other ingredients givenin Table 7, and tableted, respectively by dry'and direct compression method (pressure 2 300 kglcm Samples 7 and 8 were thereby obtained. The properties of these samples were as given in Table 8. 5O

' Table 7 Sample No. 8

Mephenesin 202 mg 200 mg Polyethylene glycol 400 50 do. 50 do. Carbowax 600 1 do. 1 do. HPC. M.S.: 0.25 100 do. 0 MC, M.S.: 0.5 0 100 do. Total weight (per tablet) 351 mg 351 mg Table 8 Sample No. 7 8

Hardness (kg) 15 kg 7 kg Average Disintegration time lmin. l min. 30 sec.

mill, until at least of it' had a particle size of 246p.

or less and it had an apparent density of 0.45 g/cc, whereby a Sample 13 was obtained or until atleast 90% of it had a particle size of 74 1. or less, and it had an apparent density of 0.60 g/cc, whereby a Sample 14 was obtained. The above-mentioned hydroxypropyl methylcellulose was dissolved in a 10% aqueous caustic soda solution and processed into a 0.1 mm thick film. The film was dried, then washed with water. It was again dried, then pulverized in a vibratory ball mill, until at least 90% of ithad a particle size of 74 or less, and it had an apparent density of 0.55 g/cc whereby a Sample 15 was obtained.

250 parts of lactose, 18 parts of polyethylene glycol, and 2 parts of calcium stearate were added to 30 parts of each of the Samples and to 30 parts of microcrystalline cellulose as a control. The mixtures thus prepared weretableted on a direct compression-type tableting machine (pressure: 300 kglcm into 300 mg. tablets. The average disintegration time and hardness of the tablets were as given in Table 10.

Table 10 Present invention Control Sample No. I6

Apparent density (glcc) 0.45 0.60 0.55

article Over 246p. 4.5 distribution v 100 74y. 22.0 91.1 89.0 Under 74p. 3.5 3.5 2.2 Result of Hardness 6.9 12.2 14.9 13.0 the test (kg) Average 90 90 80 Over 300 disintegration time (sec) What is claimed 1s: 15 4. The dosage form as claimed in claim 1 wherein l. A medicament solid dosage form comprising a medicament and l to 50% by weight, based on the weight of the medicament solid dosage form, of a cellulose ether excipient selected from the group consisting of hydroxy alkylcellulose and hydroxyalkyl-alkylcellulose, in which the average total number of substituted moles of hydroxyalkyl groups and alkyl groups per anhydrous glucose unit is 0.1 to 1.30, the average number of substituted moles of hydroxyalkyl group 'per anhydrous glucose unit is 0.05 to 1.00, and the average number of substituted moles of alkyl groups per anhydrous glucose unit is 0 to 1.00.

2. The dosage form as claimed in claim 1 wherein the average total number of substituted moles of hydroxyalkyl groups and alkyl groups per anhydrous glucose unit is 0.2 to 1.0, the average number of substituted moles of hydroxyalkyl groups per-anhydrous glucose unit is 0.10 to 0.80, and the average number of substituted-moles of alkyl groups per anhydrous glucose unit is less than 0.80.

3. The dosage form as claimed in claim 1 wherein 10 to 30% by weight of the cellulose ether excipient is present.

said hydroxyalkyl cellulose is hydroxy propyl cellulose and the average number of substituted moles of hydroxyalkyl cellulose is 0.1 to 1.0.

5 The dosage form as claimed in claim 1, wherein said cellulose ether is a powdery material, at least 90% by weight of which has a particle size not exceeding 100p, and the apparent desity of which is from 0.3 to 0.8 g/cc.

6. The dosage form as claimed in claim 1, wherein said cellulose ether is a powdery material at least 90% by weight of which has a particle size not exceeding 80p. and the apparent density of which is 0.5 0.8 g/cc.

7. The dosage form as claimed in claim 1 wherein said cellulose ether is selected from the group consisting of hydroxyethyl cellulose, hydroxypropylcellulose, hydroxybutyl ethylcellulose, hydroxybutyl methylcellulose, hydroxypropyl methylcellulose, hydroxypropylethylcellulose, hydroxyethyl ethylcellulose, hydroxyethyl methylcellulose and mixtures thereof.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2851453 *Aug 9, 1954Sep 9, 1958Smith Kline French LabCellulose derivative product, compositions comprising the same and their preparation
US3424842 *May 4, 1965Jan 28, 1969Merck Ag EManufacture of tablets directly from dry powders
US3679794 *Sep 17, 1971Jul 25, 1972Organon NvProcess for the manufacture of rapidly disintegrating solid dosage unit forms
Non-Patent Citations
Reference
1 *GA. 69 number 61529A (1968).
2 *GA. 71 number 42248h (1969).
3 *GA. 75 number 25412X (1971).
4 *GA. 75 number 40356A (1971).
5 *GA. 75 number 40419Y (1971).
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4001211 *Oct 1, 1975Jan 4, 1977The Dow Chemical CompanyPharmaceutical capsules from improved thermogelling methyl cellulose ethers
US4014541 *Apr 26, 1974Mar 29, 1977Hercules IncorporatedGolf tee
US4014675 *Dec 5, 1974Mar 29, 1977Hercules IncorporatedFertilizer stick
US4017598 *Apr 22, 1975Apr 12, 1977Shin-Etsu Chemical Company LimitedPreparation of readily disintegrable tablets
US4159346 *Aug 9, 1977Jun 26, 1979Fmc CorporationMore concentrated dosages
US4176175 *Jun 6, 1977Nov 27, 1979Shionogi & Co., Ltd.Sugar-coated solid dosage forms
US4179497 *Nov 13, 1978Dec 18, 1979Merck & Co., Inc.Pilocarpine pamoate, hydroxypropyl cellulose matrix
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US4226849 *Jun 14, 1979Oct 7, 1980Forest Laboratories Inc.Sustained release therapeutic compositions
US4258179 *Dec 20, 1978Mar 24, 1981Yamanouchi Pharmaceutical Co., Ltd.Hydrogel of water-insoluble hydroxypropyl cellulose
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US4465660 *Dec 21, 1982Aug 14, 1984Mead Johnson & CompanySustained release tablet containing at least 95 percent theophylline
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US6602995Jan 11, 2001Aug 5, 2003Shin-Etsu Chemical Co., Ltd.The reaction product of an alkali cellulose with a hydroxypropylating agent is granulated and the resulting granular material is neutralized with acid
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US7179486May 18, 2001Feb 20, 2007Nostrum Pharmaceuticals, Inc.Preparing the granulated niacin by granulating and milling a powdered form of the niacin into granules; blending with a lubricant until the lubricant is substantially evenly dispersed in the mixture and compressing the mixture into a tablet
US8303868Jan 25, 2010Nov 6, 2012Shin-Etsu Chemical Co., Ltd.Wet granulation tableting method using aqueous dispersion of low-substituted hydroxypropyl cellulose
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US8343547Aug 1, 2007Jan 1, 2013Shin-Etsu Chemical Co., Ltd.Solid dosage form comprising solid dispersion
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Classifications
U.S. Classification424/94.21, 536/90, 514/781, 536/95
International ClassificationC08L1/28, C08L1/00
Cooperative ClassificationC08L1/28
European ClassificationC08L1/28